Fuel cells are devices that are useful for generating electrical power. There are different types of fuel cells that have been developed and are under continuing investigation. Phosphoric acid fuel cells (PAFC) utilize phosphoric acid as an electrolyte for facilitating the electrochemical reaction that is used for generating electrical power.
One of the challenges associated with PAFCs is maintaining an adequate amount of phosphoric acid. It is known that the amount of phosphoric acid in a PAFC decreases over the useful lifetime of the PAFC. Proposals have been made for mitigating the reduction of phosphoric acid within a PAFC. Even with such measures, there still is a need for maintaining an adequate amount of phosphoric acid. Any attempt to extend the useful life of a PAFC requires even more phosphoric acid over the lifetime of the PAFC.
One of the challenges associated with attempting to increase the amount of phosphoric acid within a PAFC at the beginning of its life is that too much phosphoric acid can actually result in performance degradation. For example, too much phosphoric acid may prevent reactant mass transfer within the fuel cell.